treewide: future-proof frozen_string_literal changes

Once again Ruby seems ready to introduce more incompatibilities
and force busywork upon maintainers[1].  In order to avoid
incompatibilities in the future, I used the following Perl
script to prepend `frozen_string_literal: false' to every
Ruby file:

use v5.12;
use autodie;
my $usage = 'perl /path/to/script <LIST_OF_RB_FILES>';
my $fsl = "# frozen_string_literal: false\n";
for my $f (@ARGV) {
	open my $fh, '<', $f;
	my $s = do { local $/; <$fh> } // die "read($f): $!";
	next if $s =~ /^#\s*frozen_string_literal:/sm;

	# fsl must be after encoding: line if it exists:
	if ($s =~ s/^([ \t]*\#[ \t\-\*\#]+encoding:[^\n]+\n)/$1$fsl/sm
			# or after the shebang
			|| $s =~ s/^(#![^\n]+\n)/$1$fsl/
			# or after embedded switches in rackup files:
			|| ($f =~ /\.ru$/ &&
				$s =~ s/^(#\\[^\n]+\n)/$1$fsl/)
			# or prepend as a last resort:
			|| (substr($s, 0, 0) = $fsl)) {
		open $fh, '>', $f;
		print $fh $s;
		close $fh;
	}
}

Somebody interested will have to go through every Ruby source
file and enable frozen_string_literal once they've thoroughly
verified it's safe to do so.

[1] https://bugs.ruby-lang.org/issues/20205

20 files changed, 20 insertions, 0 deletions

diff --git a/test/ipv6_enabled.rb b/test/ipv6_enabled.rb
index c4c9709..84ed9c1 100644
--- a/test/ipv6_enabled.rb
+++ b/test/ipv6_enabled.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 def ipv6_enabled?
   tmp = TCPServer.new(ENV["TEST_HOST6"] || '::1', 0)
   tmp.close
diff --git a/test/rack_unicorn.rb b/test/rack_unicorn.rb
index 0ecbd42..05a7751 100644
--- a/test/rack_unicorn.rb
+++ b/test/rack_unicorn.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "test/unit"
 require "raindrops"
 require "open-uri"
diff --git a/test/test_aggregate_pmq.rb b/test/test_aggregate_pmq.rb
index 692b9bd..24e0277 100644
--- a/test/test_aggregate_pmq.rb
+++ b/test/test_aggregate_pmq.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 require "test/unit"
 require "raindrops"
 pmq = begin
diff --git a/test/test_inet_diag_socket.rb b/test/test_inet_diag_socket.rb
index a8c9973..e310dff 100644
--- a/test/test_inet_diag_socket.rb
+++ b/test/test_inet_diag_socket.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 require 'fcntl'
diff --git a/test/test_last_data_recv.rb b/test/test_last_data_recv.rb
index 9643dc6..edd00f3 100644
--- a/test/test_last_data_recv.rb
+++ b/test/test_last_data_recv.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 begin
   require 'aggregate'
   have_aggregate = true
diff --git a/test/test_last_data_recv_unicorn.rb b/test/test_last_data_recv_unicorn.rb
index 60d1be9..55f5e7f 100644
--- a/test/test_last_data_recv_unicorn.rb
+++ b/test/test_last_data_recv_unicorn.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "./test/rack_unicorn"
 require "tempfile"
 require "net/http"
diff --git a/test/test_linux.rb b/test/test_linux.rb
index 7808469..5451c3f 100644
--- a/test/test_linux.rb
+++ b/test/test_linux.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'tempfile'
 require 'raindrops'
diff --git a/test/test_linux_all_tcp_listen_stats.rb b/test/test_linux_all_tcp_listen_stats.rb
index ef1f943..12a35ba 100644
--- a/test/test_linux_all_tcp_listen_stats.rb
+++ b/test/test_linux_all_tcp_listen_stats.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'socket'
 require 'raindrops'
diff --git a/test/test_linux_all_tcp_listen_stats_leak.rb b/test/test_linux_all_tcp_listen_stats_leak.rb
index 7be46d4..a3da07e 100644
--- a/test/test_linux_all_tcp_listen_stats_leak.rb
+++ b/test/test_linux_all_tcp_listen_stats_leak.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 require 'socket'
diff --git a/test/test_linux_ipv6.rb b/test/test_linux_ipv6.rb
index 9e8730a..9ef8f0a 100644
--- a/test/test_linux_ipv6.rb
+++ b/test/test_linux_ipv6.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'tempfile'
 require 'raindrops'
diff --git a/test/test_linux_middleware.rb b/test/test_linux_middleware.rb
index f573225..7ed20df 100644
--- a/test/test_linux_middleware.rb
+++ b/test/test_linux_middleware.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'tempfile'
 require 'raindrops'
diff --git a/test/test_linux_reuseport_tcp_listen_stats.rb b/test/test_linux_reuseport_tcp_listen_stats.rb
index 4fda218..82083e0 100644
--- a/test/test_linux_reuseport_tcp_listen_stats.rb
+++ b/test/test_linux_reuseport_tcp_listen_stats.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "./test/rack_unicorn"
 require 'test/unit'
 require 'socket'
diff --git a/test/test_middleware.rb b/test/test_middleware.rb
index 56ce346..5694cd4 100644
--- a/test/test_middleware.rb
+++ b/test/test_middleware.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 
diff --git a/test/test_middleware_unicorn.rb b/test/test_middleware_unicorn.rb
index 6730d4b..53226a9 100644
--- a/test/test_middleware_unicorn.rb
+++ b/test/test_middleware_unicorn.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "./test/rack_unicorn"
 $stderr.sync = $stdout.sync = true
 
diff --git a/test/test_middleware_unicorn_ipv6.rb b/test/test_middleware_unicorn_ipv6.rb
index 3d6862c..99ecb7f 100644
--- a/test/test_middleware_unicorn_ipv6.rb
+++ b/test/test_middleware_unicorn_ipv6.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "./test/rack_unicorn"
 require "./test/ipv6_enabled"
 $stderr.sync = $stdout.sync = true
diff --git a/test/test_raindrops.rb b/test/test_raindrops.rb
index 6351c66..165766e 100644
--- a/test/test_raindrops.rb
+++ b/test/test_raindrops.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 require 'tempfile'
diff --git a/test/test_raindrops_gc.rb b/test/test_raindrops_gc.rb
index 2098129..a9f2026 100644
--- a/test/test_raindrops_gc.rb
+++ b/test/test_raindrops_gc.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 
diff --git a/test/test_struct.rb b/test/test_struct.rb
index 9792d5b..abf0c59 100644
--- a/test/test_struct.rb
+++ b/test/test_struct.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: false
 require 'test/unit'
 require 'raindrops'
 
diff --git a/test/test_tcp_info.rb b/test/test_tcp_info.rb
index 2ddacfd..2dc5c50 100644
--- a/test/test_tcp_info.rb
+++ b/test/test_tcp_info.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require 'test/unit'
 require 'tempfile'
 require 'raindrops'
diff --git a/test/test_watcher.rb b/test/test_watcher.rb
index e5d1fa2..3cf667c 100644
--- a/test/test_watcher.rb
+++ b/test/test_watcher.rb
@@ -1,4 +1,5 @@
 # -*- encoding: binary -*-
+# frozen_string_literal: false
 require "test/unit"
 require "raindrops"
 begin